Performance

For most of its brief life, Atom was the only core that beat at the heart of Chrome devices. Samsung actually brought us the first Core-based CPU with the Celeron 867 powered Series 5 550, and also the first ARM-based Chromebook with their very own Exynos 5 Dual. We didn’t have a chance to compare the results of the slightly faster clocked Samsung 550, but we do have data for the Atom-based Chromebook. What we expect from this processor is nothing less than IPC dominance. The Intel Celeron 847’s Sandy Bridge cores in the Acer C7 Chromebook are clocked at just 800 MHz, well below the 1.1 GHz possible. The low clock speed helps with battery life, of course, but still places the C7 in a position of dominance over the latest Samsung Chromebook. On the GPU front this is also the most power Chrome OS has seen, with the HD2000 being not our favorite but certainly not our least favorite integrated graphics.

How you harness all that processing and graphics power is . . . a bit limited. You won’t be launching Steam for a pick-up match in TF2 (about all I’d consider playing with the power on hand), instead everything you do will be in the browser. With technologies like WebGL and HTML5 becoming more capable of leveraging local hardware resources we are much closer to experiencing desktop-like web applications. To that end, we have a fair number of tests that show off how well Chrome OS can handle those technologies and the JavaScript tests we’re used to from our mobile tests.

Chromebook Performance Comparison

SunSpider 0.9.1

BrowserMark

RIABench Focus Tests

Kraken

Atom N570 1.66GHz

1034.3 ms

n/a

1968 ms

14229.5 ms

Exynos 5 Dual 1.7GHz

690.5 ms

3056.0

1192 ms

9733.2 ms

Celeron 847 (SNBx2) 800MHz

527.1 ms

3403.7

1194 ms

6817.2 ms

In Sunspider we see a distinct advantage for the Acer, which is no big surprise. The Exynos 5 certainly shows off an admirable advantage over the Atom-based Chromebook, but the C7 trumps that advantage soundly. The Browsermark benchmark has seen its first full update, and as always, that means we’re left with the task of reevaluating all our old hardware with the new suite. In this case we only have a few samples to compare to, so no big burden. The advantage of the C7 is smaller compared to the Sunspider score, but still quite clear. RIABench stands out as the one equalizer between the C7 and the Samsung, indicating that the bottleneck may be within Chrome’s code itself. In Kraken we see another decisive performance win for the Acer.

Chromebook Performance Comparison

IE10 Bubbles Test

IE10 Fishbowl

IE10 Maze Solver

Atom N570 1.66GHz

11 fps

5 fps

45 seconds

Exynos 5 Dual 1.7GHz

17 fps

8 fps

17 seconds

Celeron 847 (SNB) 800MHz

19 fps

17 fps

17 seconds

The Bubbles and Maze Solver tests do not involve the GPU in any considerable way, making them mostly tests of JavaScript rendering. The Fishbowl test uses HTML5 functions which can be GPU accelerated, resulting in a large performance advantage for the C7. It’s hard to say whether there is any GPU acceleration happening in the Samsung, but if so then the GPU advantage for the Acer is enormous.

Chromebook GPU Performance Comparison

WebGL Solar System

WebGL Cubes (500)

WebGL Aquarium (50)

Atom N570 1.66GHz

2 fps

10 fps

2 fps

Exynos 5 Dual 1.7GHz

22 fps

28 fps

38 fps

Celeron 847 (SNB) 800MHz

31.7 fps

30 fps

43.3 fps

The WebGL tests hint at that GPU advantage, but not so clearly as we’d like. In the Samsung Chromebook review, Anand discussed how desperately Atom’s GMA-3150 GPU needs to see a huge update to be competitive. Samsung’s use of the Mali-604T in their Chromebook gives it a huge advantage over Atom. The HD2000-based graphics in the Acer C7 show how far mobile SoC GPUs still have to go to compete with PC derived GPUs. We’re limited by an inability to disable Vsync, but if we could I think we would see a much larger advantage than what we see now. We want to explore these differences further soon, but for now all you need to know is that anything that can be processed by the GPU will do much better on the C7 than the Samsung.

MHz does matter. Sandy Bridge is not optimized to actively run at 800MHz - its sweet spot is around 3GHz. You pay a huge perf/watt penalty through leakage. An i7 doing the same tasks can go to sleep and power gate in 1/4 the time.Reply

I think it could be the case that making an architectural change yields significant benefits, however after you while you'd end up like Intel, spending a huge amount of money to eke out a few more percent. I doubt that the next big step for ARM would be anything like A9 to A15 was.Reply

I know when I saw the benchmarks I had to go back and look at the x86 specs. For a second I thought the A15 was way faster than I expected. But then I saw just how crippled the celeron is and everything made sense...Reply

Others pointed this out, but the take away from performance a performance standpoint is that if you take the second fastest x86 core designs in the market today, gut them, take out their legs, wrap a chain around their neck and put blinders on them, they're still faster than the fastest ARM Cortex-based SoC on the market today.

The big play with A15 is that they have finally reached IPC parity with small notebooks. And while that would have definitely been true 5 years ago when Atom was still fresh and Sandy Bridge was off the edge of Intel's road map slides, it is now not nearly so strong a case. In terms of performance/watt, ARM has done a very very good thing and they should be commended for that. And I have no doubt that a Chromebook equipped with Exynos 5 clocked at 2.3GHz would wipe the floor with the Acer C7. But we're still talking about putting a featherweight champion against a heavyweight punching bag.

We'll explore this relationship a little further, indeed you can get some feel of it in Anand's reviews of the Win8 tablets that have been coming out. Stay tuned. Reply

Hmm, but the graphics are an important point, and it seems like ARM (Mali-series) and Nvidia have a better roadmap there. Maybe a T4 Chromebook could take down an Ivy or Haswell ULP? Or an Exynos-Quad?

Never mind the fact that this product, in similar fashion to the Droid phones, is designed entirely with the focus of mining, harvesting, and exploiting your personal data for their profit. No thank you, Google. Hell, I'll pay the Dell/HP "premium" of a $299 or $399 laptop/ultrabook to avoid that whole arrangement. Mind you, I've already happily paid the Apple premium to have devices focused on my ease of using them rather than the ease of which my information is exploited. Apple has a much better track record in respecting user's privacy, making the disclosure of it voluntary rather than inherent to the products being used.Reply